This invention relates generally to a novel processing architecture for use in multimedia applications, and more particularly to a processing architecture and associated method adapted to decompress compressed digital video and audio data, processes the digital video and audio data, as well as other digital data, and generate high resolution color multimedia data for presentation on a computer system or other suitable multimedia presentation system.
Compression of full-motion digital images to facilitate storage of the digital video images on a relatively narrow bandwidth media, such as a DVD, a CD, or a computer memory, is known. A typical single full image video frame for a computer screen consists of over 300,000 pixels, where each pixel is defined by one of 16.7 million colors in a 24 bit color system. This single full color image frame may be stored in approximately 1 million bytes (1 Mb) of memory. To achieve animation in an application, such as a video game, a video system should generate and display about 30 color frames per second. Thus, for one minute of full-motion, color video, the system preferably should be able to store two gigabytes (2 Gb) of image data. Similarly, a full color, still frame image scanned at 300 dots per inch requires in excess of twenty-five (25) megabytes of memory. These memory requirements are extraordinary large, and storage devices capable of storing that much data are expensive.
Furthermore, the rate at which the full color image data needs to be retrieved from the storage device in order to generate full-motion color images exceeds the effective data transfer rate of most existing storage devices. For example, assuming that a typical storage device can transfer data at a rate of about 250 KB per second, the retrieval of full-motion color video images at the necessary rate of 30 MB per second (thirty 1 MB frames per second) cannot be accomplished. This hypothetical storage device is 120 times too slow.
Therefore, image compression techniques that can reduce the amount of data required to represent a full color image, while retaining sufficiently high quality images were developed. In most of these techniques, the amount of image data is reduced by identifying places where information may be removed without significant image quality loss (i.e., where the human eye is not as sensitive). For example, the human eye is more sensitive to black and white detail than to color detail. Thus, many known techniques reduce the amount of color information about each pixel in a image without any significant perceptible reduction in the image quality.
These known compression techniques include differential pulse code modulation, Motion Picture Experts Group (MPEG) compression, and MPEG-2 compression. The MPEG format was intended to be a standard for compression and decompression of digital full-motion video and audio data for use in computer systems. The MPEG-2 format is an extension of the MPEG format that supports digital, flexible, scalable video transport. The MPEG and MPEG-2 formats are becoming the standard technique for compressing and decompressing full-motion video signals.
Once an image is compressed using these techniques, the compressed image data then typically is decompressed, and in some instances processed, in order to display the images. The decompression and processing of the compressed image data requires a large amount of processing power and also requires a large amount of memory. A conventional system for decoding/decompressing a compressed digital video image includes a memory that holds both the compressed digital video image as well as the uncompressed digital video image, and a decoder for decompressing the image and storing the image within the memory. The known decompression systems may be used in PCs, DVD players, digital satellite television systems, and cable television systems, to name but a few applications. These known systems use memory intensive operations to decode the compressed images and typically require at least 2 MB of storage space. As one skilled in the art will appreciate, these systems tend to be expensive due to the large amount of memory required for decompression. Moreover, these systems only decompress the images and do not process digital data from other sources in order to generate composite images. Finally, in order to decompress the data and simultaneously process through video data, additional memory and processing power is needed, which typically is not available in conventional video decompression systems.
In addition, conventional processing systems exist that have sufficient processing power to generate video images, but none of these systems are optimized to decompress and process full-motion color images quickly and efficiently. Typically, these processing systems also require a separate decompression system that is attached to the processing system.
Finally, none of these conventional systems decompress and process media data quickly enough for applications, such as full-motion color video games, virtual reality systems, and cable television receivers. And, none of these systems provide an inexpensive, fully functional media processing system, because none of the conventional systems include both an integrated full-motion image data decompression and processing system.
Thus, there is a need for a media processing system and method which avoids these and other problems of known devices.